1 files changed, 53 insertions, 0 deletions
diff --git a/kernel/vmem.c b/kernel/vmem.c
index a1ee0e2..d99f6fd 100644
--- a/kernel/vmem.c
+++ b/kernel/vmem.c
@@ -212,6 +212,53 @@ static void vmem_clear_one(pdirectory* dir,uint32_t virt)
 	}
 }
 
+
+// addresses need to be page aligned. (or will be forced down)
+static void vmem_del_generic(pdirectory* dir, uint32_t virt,uint32_t pages, bool dealloc, bool user)
+{
+    //fixme("make sure the pages are marked as used in the physical mem manager, really?");
+    
+    //force align
+    virt/=4096;
+    virt*=4096;
+
+    while(pages>0)
+    {
+	pd_entry* entry = &dir->m_entries [PAGE_DIRECTORY_INDEX (virt) ];
+	ptable* table;
+
+	if(*entry==0){
+	    // no pagetable here yet.
+            kpanic("no pagetable found for vmem entry to delete!");
+	}
+	else{
+	    // we use the existing one.
+	    table= pd_entry_get_frame (entry);
+	}
+
+	if(dealloc)
+	{
+	    uint32_t page=table->m_entries [PAGE_TABLE_INDEX (virt) ];
+	    uint32_t phys=pt_entry_get_frame(page);
+            mem_free_block(phys); // free the space
+	}
+
+	//zero  page
+	pt_entry page=0;
+
+	//set the page table
+	uint32_t old=table->m_entries [PAGE_TABLE_INDEX (virt) ];
+
+	if(old==0)kpanic("nothing to delete in vmem at 0x%08x",virt);
+
+	table->m_entries [PAGE_TABLE_INDEX (virt) ] = page;
+
+	virt+=4096;
+
+	pages--;
+    }
+}
+
 // addresses need to be page aligned. (or will be forced down)
 static void vmem_add_generic(pdirectory* dir,uint32_t phys,uint32_t virt,uint32_t pages, bool alloc, bool user)
 {
@@ -317,6 +364,12 @@ pdirectory* vmem_kernel_dir()
     return dir;
 }
 
+void vmem_add_framebuffer(pdirectory *dir)
+{
+    vmem_del_generic(dir,VMEM_USER_FRAMEBUFFER,VMEM_USER_FRAMEBUFFER_PAGES,false, true);
+    vmem_add_alloc(dir,  VMEM_USER_FRAMEBUFFER,VMEM_USER_FRAMEBUFFER_PAGES,true); /// each new process gets a 640x480x32 area
+}
+
 void vmem_free_space_dir(pdirectory *dir,bool stack_only)
 {